Means for maintaining the prime in pumps



Feb; 15, 1927.

' Filed Nov. 16, 1923 I' ATTOR EY, '1

Patented Feb. 15, 1927. I 1,617,422. UNITED STATES PATENT OFFICE.

, LEWIS L. score, on ST. LOUIS, MISSOURILASSIGNOR To-ELRoTRoL, INo. OF MISSOURI,

- or ST. LOUIS, MIssoURI, A CORPORATION or MISsoU I.

MEANS FOR MAINTAINiNG THE PR ME IN PUMPS. Application filed Neve'mber 16, 1923. Serial No. 675,148.

This invention relates to certain new and with a fan casing 6; and air is forced from 55 useful improvements applicable particularly said casing through the duct 4 byza fan 7. to domestic oil burners, such as described, The duct 4 and fan casing maybe supportedfor example, -in my pending application, in any suitable manner, as by means of 5 Serial No 538,559 and has for its'special standards 8, secured at their upper ends in object the provision of means for preventbrackets 9 'on the Sides of the outlet end of 60 ing the loss of prime of the oil pump used thepump casing. The fan 7 is driven by a Y for supplying th oil to the burner. motor 10, and the shaft 11 of said motor is The domestic oil burner to which my incommon to the fan 7 and to'a gear pump 12. vention relates is of the non-gravity type, The numeral 13 indicates the main oil and, in such systems, the main fuel supply supply tank, extending into .which is'a pipe 65 tank is usually-*buried underground, an 14, which communicates with the, interior fuel is lifted at distances, varying from five of the-tanknear the bottom thereof, andto ten feet'in height, by a pump and delivhas a coupled member forminga-continua-f 15 .ered to the fuel nozzle of the burner, locattion thereof, which isconnected to a supply" ed within a suitable furnace. pipe 15, leading to the inlet side of the pump 70 In the interest of quietness, efliciency and 12, in the length of which maybe located economy in operation, it has been found dea small drain reservoir 16 and a. check sirable, if not actually necessary, to use a valve 17. I

' 20 pump of thegear type, and where this type In Order to start the gearpumpinitihlly, it

of pump is used, it has been found. that unis necessary to provide a plunger pump, such.75 less suitable preventive means are employed, as indicated at 18, haviri a hand opr'eratedthey will lose their prime when shut down plungeiylt). This pump is of the ordinary for a few hours-and become, therefore, inconstruction and operates in connectionwith 2 operative until they are again primed by the check..valve 17. A hand-operated valve some suitable means. 20 is used to open-andclose communication 80 My invention overcomes this disadvantage between the pump and the pipe 15. by providing suitable means, operating auto- In operation, the gear pump '12 pumps matically, for-preserving the prime of the an excessoffuel, that is, more than isre- I pump for indefinite periods of time whenthe gun-ed for the burner .itself,-and this excess pump is not being operated. 1s. by-passed back to the main fuel tank ,85

Other objects of the invention relate to the througlr a by-pass pipe .21 communicating construction involved, hereby the principal with the pipe 5. The by-pass is regulated object of the invention is attained. is A by ashand-operated valve 22, and by regu- The invention is illustrated in the accomlating this valve, the'fuel' pressure at the W panying drawing, in which fuel nozzle within the furniiceis adjusted. on

Figure 1 is a diagrammatic View, partlyorder to accomplish the'p'urpose of prein elevation and partly in theoretical secserving the prime in the pump 12, I provide tion, illustrating a domestic oil burning sysa small tank 23 which can be anywhere 40 tom, and the construction embodying my infrom one to five gallons in capacity, and I 'vention; and a lead the by-pass pipe 21' to this tank and con- Figure 2 is a plan view of a combined oil nect it with the same near the bottom therepump and blower. of. This tank is placed slightly above the Referring now to the-drawing, the numeral discharge of the pump through pipe 5, as 45 1 indicates a furnace, such as ordinarily shown. From the top portion of the tank used for heating purposes in houses, and 23, an overflow pipe 24 leads back to the having the usual fuel opening closed by a main fuel tank, and preferably is connected, door 2. Mounted on this door, in any suitfor this purpose, to a vent pipe 25, which able manner and communicating with the communicates with the top of the main fuel 50 interior of the furnace, is anoil burner 3, of supply tank 13.

any suitable type adapted to produce a com- In operation, it will be seen that the bybustion of mixed oilnnd air, said burner be'-, passed oil discharged through pipe 21 must ing fed with air from a duct, 4, and 'with oil first fill the tank 23 to the level of the overfrom apipe 5. The air duct 4 communicates flow pipe 24: before the oil can return to the taiik 13, andhence theauxiliaryv tan} 23 will always be automatically maintained 1 full of oil, or substantially so.

a Iv claim:

It will further be, seen that the provision of the auxiliary ,tank 23 will operate to always keep the: pump and the fuel lines full of fuel, and will not permit air to enter,

so that the pump will always preserve its prime and willbe in condition to operate to pump oil to the burner Whenever the motor is started,

1. In an oil burning system of the type described, involving a source of liquid fuel located above the leyel of the suction pipe running to the fuel supply and of the diso charge outlet of said pump and communicating therewith, whereby to maintain fuel in a i l iary reservoir located above the level of'the' theifuel line and pump when the latterfis not in operation described, including a fuel pumpanda, i-pe Tus- I discharge of the pump, a by-pass connecting pipe 1plpe and reservoir, and an overflow eading from said tank and communieating with the source of fuel supply.

3. In an oil burning system of the type said described, in combination with a'main source of li uid fuel, means, including a pump, for

:with rawing fuel from said source and del vering 1t to a point of combustion, a valvecontrolled by-pass communicating with the discharge end of the pump, an auxiliary res erv'oir connected with said by-pass and lo cated above the level of the discharge'of the pump, and an overflow conduit leading from said auxiliary reservoir to the niainsourcc of fuel supply. 7

4. In an oil burning system in which oil is withdrawn by a pump from a source located below the level of the pump and delivered to a point of combustion, the method of maintaining the prime in the pump which consists in diverting a portion of the oil dclivered by the pump and storing thesamc.

above the suction line of the pump, and

maintaining constant communication between the stored oil and the pump.

5. In anoil burning system, the method which consists in pumping oil from a source, and continuously deliveringa portion of the pumped oil to a point of combustion and a portion to a point of storage located above the level of the suction line of the pump, and preserving the prime intthe pump by main- .taining communication between the stored I J :"hqu-id and the pump at all times. 2. In an oilburning system of the type:

A "6'; In a pumping system involving a source of liquid supply and a pump located above the liquid supply and having a suction pipe' running to saidliquid supply for withdrawing liquid therefrom anddelivering it, an

auxiliary reservoir of liquid located above the level of the suction pipe running to the liquid supply and of the discharge outlet of said pump and communicating therewith, whereby to maintain liquid'in the liquid line and pump when. the latter is not 'in operation.

In testimony whereof I have hereunto set n'iy'hand.

ewis L. scorn 

